The primary objectives of a chain lubricator are to (1) apply lubrication to rubbing surfaces of the chain, (2) avoid application oi excess lubrication or foreign material, and (3) be removable when lubrication is not required. The lubricator should be small so that it will not interfere with chain operation. It should also be light weight, rugged in construction, reliable, pleasing in appearance and low in cost. When the lubricator is installed or removed, a minimum of effort is also desirable.
Most of the current bicycle chain lubricators may do one of these objectives well, but other objectives and desires are not fully met. Most commonly, lubrication is accomplished by immersing or spraying a liquid lubricant on the chain. The immersion and/or spraying is sometimes also accompanied by cleaning means (wiping, brushing, etc.) to remove excess lubricant, old lubricant and dirt from the chain. This type of lubricator is commonly hand held, but may also be attached to the bicycle frame, allowing continuous lubrication. An attached device of this type is illustrated by: U.S. Pat. No. 613,833. Separate cleaning means, such as illustrated in U.S. Pat. Nos. 602,000 and 648,866, may also be used in conjunction with this type of lubricator.
A second type of lubricator saturates an absorbent material or sponge With a liquid lubricant and the absorbent material is placed in contact with the chain. The absorbent material may be in contact with a fluid reservoir to replenish liquid lubricant and may also be combined with cleaning brushes, as before. This device may also be hand held, or attached to the bicycle frame for continuous lubrication. Continuous attached lubrication devices are illustrated by U.S. Pat. Nos. 603,654; 4,593,923; and 4,194,413.
All of tbese prior art continuous chain lubricators are attached or fixed relative to the frame, allowing the chain to run in contact with the lubricant or absorbent material containing the liquid lubricant. Liquid lubricant is always used in order to migrate and lubricate unexposed surfaces, such as the pinned chain connectors.
Solid lubricants for chains are also known, but not in conjunction with continuous lubricators. Solid lubricants may have advantages over liquid lubricants in the area of reduced attraction/retention of dirt, reduced contamination of adjoining unlubricated surfaces and acting as a protective covering (e.g., corrosion protection). However, direct application of solid lubricant to an assembled chain essentially impossible because of tbe unexposed pinned connections. Whereas the liquid lubricant will migrate to unexposed surfaces by surface tension, a solid lubricant must be directly applied proximate the rubbing surfaces.
Other types of lubricators used to lubricate rope, shafts, cables or wire are known that use solid lubricants and lubricating means adapted to use solid lubricants. However, continuous solid lubricators are not appropriate to chains. Chain lubricant must lubricate tbe exposed and unexposed (pinned connections) surfaces of the chain. Wire, shaft, rope or cable lubricators lubricate only the exposed surface which directly rubs and contacts pulleys or other interfacing mechanisms.
In addition, other types of lubricators cannot properly function on a chain because the chain location between pulley/sprocket position can vary as a function of chain tension, making contact with the a fixed lubricator unreliable. Examples of shaft, rope, wire or cable lubricators which are not applicable to chain lubrication applications are illustrated in U.S. Pat. Nos. 1,584,704; 1,471,583; 296,440; 2,847,880; 2,441,642; 2,435,120; and l,049,170.
Applicable prior art continuous attached chain lubricator approaches have many limitations. These limitations are primarily related to the multiplicity of elements and type of lubricant required to accomplish the continuous lubrication function. The multiplicity of elements, weight and space particularly detract from bicycle racing applications, creating added cost, weight and space. The frame attachment and removal means can be particularly cumbersome. Lubricator entry and exit transition sections may be required to guide the chain into and out of the fixed lubricator position. Liquid lubricant also tends to attract dirt as well as drip and contaminate other surfaces if not wiped or cleaned. Cleaning or wiping means consume still further weight, attachment/removal effort, and further reduce reliability.
None of the prior art continuous chain lubricators known to the applicant avoids fixing the lubricator position with respect to the frame or uses other than a liquid lubricant.
What is needed is a simple lubricator, capable of using a solid lubricant and not requiring fixing into position relative to the frame. The unfixed position would allow the lubricator to follow movements of the chain, avoiding transition sections and associated attachment and other hardware.